A rectangular hydrogen-terminated diamond piston plate moves
back and forth inside a cavity whose walls also consist of hydrogen-terminated
diamond. The outward-facing surface of the piston plate and the inward-facing
surfaces of the piston cavity are exposed directly to the external solvent environment.
A molecular dynamics simulation of hexadecane wetting the Au(001) surface at
315 K shows that the initial monolayer is complete in ~1 x 10-9 sec [3217];
another simulation study of liquid octane near a waxy interface required ~0.4
x 10-9 sec for monolayer adsorption equilibration [3232],
and equilibration times of 0.3-1 x 10-9 sec are typical in alkane film adsorption
or confined liquid studies [3185]. For
our assembler design, we assume that predominantly n-octane molecules physisorb
to the passivated diamond walls in a time tadsorb ~ 1 x 10-9 sec << tpiston
= (2 npiston)-1 = 50 x 10-9 sec. Hence, throughout each return stroke of the
piston (wherein the cavity is reduced to zero volume), all cavity walls that
are still exposed to solvent should be reliably coated with a complete physisorbed
monolayer of n-octane molecules.